ungrounding brushes?

what brushes, where?

 

What brushes? There is an alternator that has 3 white wires to the rectifier and a field coil with normally a black and a green wire (green to the regulator). The starter motor has brushes but nothing else I think?

 

Sorry Drew, didn't notice your reply.

 

There should be continuity between the green and black wires for the coil to work as it is basically one long wire with a voltage running through it. Do you mean there is a short between the wires before it reaches the field coil so the coil is not exciting? Where are you testing the coil? You can test it by taking off the round alternator cover but you will lose some oil.

 

In a nutshell, you should be testing resistance not continuity

field winding should be about 4 ohms green/green or green/black

3 white wires to stator each one in sucession .72 ohms

variations will occur proportionate to the temperature

 

what exactly is your problem? alternator is nothing to do with the plugs/coils.

your getting me confused now

have we answered your first question?

 

The XS650 only needs to unground the brushes if you put an 80 up reg/rec onto a 70-79 bike. It has nothing to due with running just a kick start or simplfied wiring. I have not spent much time studying the XS400 but I assume the systems are simular.
On your 77 does it have separate regulator and recifier?
I'll check a parts fiche and see what it looks like.
In the parts fiche it shows a stator and a feild coil with a rotor tjhat spins between them. No brushes.
It does have a separate reg and rec. The way it looks you can replace the separate units for the combo unit with out too much trouble. I'll look at a wiring diagram and get back with you.
Leo

 

From looking at the diagrams it looks like a pretty much a straight up swap to convert from the older mechanical reg and rec to the later combo reg/rec. Or due the Chrysler/ Radio Shack conversion.
Research them on 650.com.
Leo